Aulacus bicolor Jennings & Austin, 2018

Jennings, John T., Parslow, Ben A. & Austin, Andrew D., 2018, Systematics of the parasitoid wasp genus Aulacus Jurine (Hymenoptera: Evanioidea: Aulacidae) from Australia, Zootaxa 4538 (1), pp. 1-113 : 22-24

Aulacus bicolor Jennings & Austin , sp. nov.

Figs 9 , 56 .

Material examined. Holotype. ♀, " Fernvale , Qld. Australia Nov–Dec " ( ANIC) . Paratypes. Queensland: 1♀, same data as holotype ( AEI) ; 1♀, Talegalla Weir Junction , 35 m, 25.757’ S 152.695 ’E, 22.xi-7.xii.2011, G. Monteith ( QM) ; 1♀, Fraser Island , 11-14.x.1978, GB Monteith ( QM) . NSW: 1♀, Breakneck lookout, 11 km SSW Taree, 13- 24 xi.1991, G & T Williams ( AMS) .

Description. FEMALE. Length. 9.9 (9.6–10.2) mm, excluding ovipositor.

Colour. Head black ( Figs 9A, B ), mandibles largely brown, antenna orange except last two flagellomeres black, mesothorax pale orange in the anterior half and largely black in the posterior half, scutellum and mesopleuron orange, axillae, metapostnotum, mesepimeron, and metapleuron dark brown, variable amounts of dark brown on propodeum, fore and mid tarsomeres 4–5 and claw black, hind legs dark brown except for variable amounts of orange on coxae. Wings hyaline except for large brown spot apically on marginal and submarginal cells of fore wing, and brown band either side of fore wing veins 1-Rs and 1-M and apically in costal cell ( Figs 9A, B ).

Head. 1.36 (1.30–1.42)× wider than long when viewed dorsally ( Fig. 9C ); face punctate-reticulate, pubescence long; shallow sub-antennal groove; frons punctate-reticulate, without lateral medial carina above toruli, pubescence long; vertex and gena punctate-reticulate, pubescence long; posterior margin of head not concave in dorsal view; occipital carina absent; malar space 0.22× height eye; clypeus 4.6× as wide as high, margin sinuate, with medial process; distance from lateral ocellus to eye margin 0.6× distance between lateral ocelli; scape 1.5× length pedicel; first flagellomere 1.8× as long as scape, 0.5× as long as second flagellomere.

Mesosoma. Propleuron rugose, pubescence long, ventro-lateral carina present; pronotum reticulate dorsally, rugose ventrally, mesoscutum in lateral view somewhat angular antero-dorsally ( Fig. 9E ), medial and lateral lobes strigate, with scattered short setae, admedial lines present; notauli distinct, carinate, narrow and deep; scutellum and axillae strigate, scutellum anteriorly with pair of deep depressions, separated by a median carina; metapostnotum scrobiculate, posterior margin slightly curved; mesopleuron rugulose dorsally, coarsely rugose ventrally, pubescence long; mesepimeron broad, carinate; metapleuron coarsely rugose, pubescence short; propodeum coarsely rugose, posterior margin weakly scrobiculate; hind coxa strigate dorsally, pubescence long laterally, ovipositor guide somewhat medial, oblique, no fringe of long setae distally, smooth inside groove ( Fig. 9F ); hind trochanter imbricate, with scattered short setae; prefemur on hind leg present; hind femur imbricate, with scattered short setae; hind tibia imbricate, pubescence short, with scattered stout emergent setae; hind femur 1.40 (1.37–1.44)× length hind tibia; hind tibia with ventro-apical pecten of short robust spines; hind tarsomeres 1–4 with ventro-apical pecten of short robust spines, tarsomere 1, 2.6× length tarsomere 2; tarsomere 2, 1.6× length tarsomere 3; tarsomere 3, 2.3× length tarsomere 4; tarsomere 4, 0.6× length tarsomere 5; hind tarsal claw 0.4× length tarsomere 5; fore wing vein 2-Rs+M very long, veins 2r-m and 3r-m largely spectral; hind wing venation complete, R+Rs, M+Cu, Cu, r-m and 2-M spectral, with 3 hamuli.

Metasoma. Clavate, 1.57 (1.52–1.62)× length of mesosoma; T1 and T2 narrow, glabrous; ovipositor 9.70 (9.40–10.00) mm.

MALE. Unknown.

Etymology. This species is so named because of the distinctive colouration of the mesothorax, being pale orange in the anterior half and largely dark brown in the posterior half.

Distribution. This species is known from several localities in Queensland and NSW over a distance of some 1,600 km ( Fig. 56 ).

Biology. The specimen from near Taree, NSW, emerged from a dead branch of Backhousia sciadophora (Myrtaceae) .

Comments. Aulacus bicolor is one of a number of species with the mesoscutum angular in lateral view, but is the only one of these species with a clavate metasoma. Aulacus bicolor also has the face punctate-reticulate and fore wing vein 2-Rs+M very long.

The distinctive colouration of the mesothorax of this species distinguishes it from other Australian Aulacus species.

Figures

FIGURE 9. Aulacus bicolor sp. nov., holotype female, (A) dorsal habitus; (B) lateral habitus; (C) dorsal head; (D) dorsal mesosoma and metasomal T1 and T2; (E) lateral mesosoma; (F) inner lateral right hind coxa.

FIGURE 56. Distribution of Aulacus atriceps Kieffer, A. bamagensis sp. nov., A. bashfordi sp. nov., and A. bicolor sp. nov.